1-Chloro-3,3,3-trifluoropropene (HCFC-1233zd) is a raw material used for making 1,1,1,3,3-pentafluoropropane (HFC-245fa). However, it also has other uses, such as for example, as a monomer in the preparation of polymeric materials. It can also be used as a raw material as a building block for making other fluorinated compounds. The preparation of HFC-245fa from HCFC-12333zd is a two-step process, such as disclosed in WO 97/24307. In this two-step process 1,1,1-3,3-pentachloropropane (HCC-240fa) first reacts, in the gas phase, with hydrogen fluoride to give 1233zd, which, after the removal of HCl formed, reacts in a second step with hydrogen fluoride to give HFC-245fa. This gaseous phase reaction is generally carried out at temperatures of 180° C. or higher, preferably higher. In another process disclosed in U.S. Pat. No. 6,362,383, it is taught that the production of HFC-245fa at about 120° C. can be improved by first reacting HCC-240fa with hydrogen fluoride in liquid phase in the presence of a hydrofluorination catalyst to produce HCFC-1233zd and other reaction products, and in a second step the HCFC-1233zd obtained from the first step is reacted with hydrogen fluoride in liquid phase in the presence of a second hydrofluorination catalyst to obtain the HFC-245fa, wherein in at least one or both of the steps there is the continuous introduction of hydrogen chloride into the reaction medium. In Example 1 of this patent, the first step of the reaction, with the introduction of hydrogen chloride, produces HCFC-1233zd as only 3.3% of the reaction products after 2.5 hours and 1.55% of the reaction products after 22 hours. In the second Example in this patent, when HCl is not continuously fed into the reaction medium, the production of HCFC-1233zd in the first step after 2.5 hours is 64.6% and after 22 hours is 11.9% of the reaction products. This prior art teaches introduction of hydrogen chloride to the reaction mixture to minimize formation of HCFC-1233zd.
In view of the other substantial markets for HCFC-1233zd there is a need for the ability to produce HCFC-1233zd in as high a yield as possible, and in greater yields than shown to be possible in U.S. Pat. No. 6,362,383. Moreover, it is also desirable to be able to produce HCFC-1233zd in high yield in a process that is able to utilize low reaction temperatures of 150° C. or less, preferably less, so that high pressure and the need for expensive equipment can be avoided. Moreover, it is highly desirable that such a process be available that produces HCFC-1233zd in increased higher yields so that large amounts of by-products can be avoided.